An automated flow calorimeter for the determination of liquid and vapor isobaric heat capacities: Test results for water and n‐pentane

AbstractFast chemical process development is inevitably linked to an optimized determination of thermokinetic data of chemical reactions. A miniaturized flow calorimeter enables increased sensitivity when examining small amounts of reactants in a short time compared to traditional batch equipment. Therefore, a methodology to determine optimal reaction conditions for calorimetric measurement experiments was developed and is presented in this contribution. Within the methodology, short-cut calculations are supplemented by computational fluid dynamics (CFD) simulations for a better representation of the hydrodynamics within the microreactor. This approach leads to the effective design of experiments. Unfavourable experimental conditions for kinetics experiments are determined in advance and therefore, need not to be considered during design of experiments. The methodology is tested for an instantaneous acid-base reaction. Good agreement of simulations was obtained with experimental data. Thus, the prediction of the hydrodynamics is enabled and the first steps towards a digital twin of the calorimeter are performed. The flow rates proposed by the methodology are tested for the determination of reaction enthalpy and showed that reasonable experimental settings resulted. Graphical abstract A methodology is suggested to evaluate optimal reaction conditions for efficientacquisition of kinetic data. The experimental design space is limited by thestepwise determination of important time scales based on specified input data.

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Interaction Boundary Determination of Renewable Energy Sources to Estimate System Strength Using the Power Flow Tracing Strategy

Sustainability ◽

10.3390/su13031569 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1569

Author(s):

Namki Choi ◽

Byongjun Lee ◽

Dohyuk Kim ◽

Suchul Nam

Keyword(s):

Renewable Energy ◽

Power Flow ◽

Renewable Energy Sources ◽

Energy Sources ◽

Test Results ◽

Boundary Determination ◽

Actual Interaction ◽

Power Flow Tracing ◽

Estimate System

System strength is an important concept in the integration of renewable energy sources (RESs). However, evaluating system strength is becoming more ambiguous due to the interaction of RESs. This paper proposes a novel scheme to define the actual interaction boundaries of RESs using the power flow tracing strategy. Based on the proposed method, the interaction boundaries of RESs were identified at the southwest side of Korea Electric Power Corporation (KEPCO) systems. The test results show that the proposed approach always provides the identical interaction boundaries of RESs in KEPCO systems, compared to the Electric Reliability Council of Texas (ERCOT) method. The consistent boundaries could be a guideline for power-system planners to assess more accurate system strength, considering the actual interactions of the RESs.

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Direct determination of enthalpy of mixing for the binary gaseous system methane-carbon dioxide by an isothermal flow calorimeter

Journal of Chemical & Engineering Data ◽

10.1021/je00029a010 ◽

1982 ◽

Vol 27 (3) ◽

pp. 258-264 ◽

Cited By ~ 13

Author(s):

Alpha O. Barry ◽

Serge C. Kaliaguine ◽

Rubens S. Ramalho

Keyword(s):

Carbon Dioxide ◽

Direct Determination ◽

Enthalpy Of Mixing ◽

Isothermal Flow ◽

Flow Calorimeter ◽

Methane Carbon

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High Strength Combined Support Technology in Deep High Stress Soft Rock Roadway

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.598 ◽

2012 ◽

Vol 524-527 ◽

pp. 598-603

Author(s):

Nian Jie Ma ◽

Zhi Qiang Zhao ◽

Hua Zhao ◽

Li Shuai Jiang

Keyword(s):

High Stress ◽

Soft Rock ◽

High Strength ◽

Parameter Determination ◽

Test Results ◽

Actual Measurement ◽

Computer Numerical Simulation ◽

Soft Rock Roadway ◽

Rock Roadway

In order to solve the serious damage and repeat revision problem of high stress soft rock roadway in deep -950 level of Tangshan coal mine, based on the theory of the maximum stress level, together with the actual measurement of geostress and the laboratory mechanical parameters of rock-core and computer numerical simulation, the high strength combined support technology and supporting parameters are determined and the engineering test has been done. The engineering test results show that the parameter determination of high strength combined support technology, which based on the actual measurement of geostress, can effective solve the support issue of high stress soft rock roadway and provide useful experience for similar engineering problems.

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Experimental and Theoretical Rotordynamic Characteristics of a Hybrid Journal Bearing

Journal of Tribology ◽

10.1115/1.2832446 ◽

1997 ◽

Vol 119 (1) ◽

pp. 132-141 ◽

Cited By ~ 17

Author(s):

J. T. Sawicki ◽

R. J. Capaldi ◽

M. L. Adams

Keyword(s):

Journal Bearing ◽

Operating Conditions ◽

Dynamic Force ◽

Test Results ◽

Force Measurements ◽

Lubrication Equation ◽

Load Cells ◽

Theoretical Predictions ◽

Stiffness And Damping

This paper describes an experimental and theoretical investigation of a four-pocket, oil-fed, orifice-compensated hydrostatic bearing including the hybrid effects of journal rotation. The test apparatus incorporates a double-spool-shaft spindle which permits independent control over the journal spin speed and the frequency of an adjustable-magnitude circular orbit, for both forward and backward whirling. This configuration yields data that enables determination of the full linear anisotropic rotordynamic model. The dynamic force measurements were made simultaneously with two independent systems, one with piezoelectric load cells and the other with strain gage load cells. Theoretical predictions are made for the same configuration and operating conditions as the test matrix using a finite-difference solver of Reynolds lubrication equation. The computational results agree well with test results, theoretical predictions of stiffness and damping coefficients are typically within thirty percent of the experimental results.

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